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By J. F. Myers, F. M. Lewis

IN the mining and handling of sulphide ores, some degree of oxidation takes place on the sulphide surfaces, which are exposed to the atmosphere. It is, moreover, well known that the oxidation compounds formed are a factor when such ores are subsequently treated by flotation. Modern operating technique and reagents are capable of contending with this condition to a major degree, provided that the proportions of the reagents used are varied correctly. This is particularly true at the Tennessee Copper Co., where the ore treated contains pyrrhotite in addition to other sulphides. A number of soluble salts, some of which are unstable, can be formed during the oxidation of the sulphide ores. Those unstable salts, whose oxygen requirements are unsatisfied, are constantly changing to more stable forms because oxygen reacts with them during the crushing, grinding and other operations of ore preparation. We add no chemicals of any kind to the ore pulp in its preparation for flotation feed. Consequently the only compounds that are present in the flotation feed are those produced by the natural oxidation of the ore in the presence of air and water. The Tennessee Copper Co. ore is composed of from 60 to 70 per cent sulphides and from 40 to 30 per cent nonsulphide material. It is not the purpose of this paper to discuss the nature of these various oxygensulphur compounds nor their effect on flotation, but to describe a method for [ ] correcting the effect. Suffice it to say that we have found that the reducing sulphur and oxygen salts have a depressing action on our bulk flotation process.1 From long experience we find that the best means of correcting for this variation in our work is to increase or decrease the quantity of xanthate, the promoting agent, as the quantity of the reducing salts increases or decreases. It was, therefore, very desirable to provide the operators with some quick and

Jan 1, 1946

By R. W. Dr. Raymond

(Read at the Philadelphia Meeting, February, 1878.) THE manufacture of ferromanganese in the blast furnace having been the subject of considerable attention in the Institute, I beg to put on record a contribution to the discussion from a quarter hitherto not directly represented, namely, the St. Louis furnaces, near Marseilles in France, belonging to a company of which M. Jordan, a member of the Institute, is Managing Director. These furnaces commenced in 1862 to manufacture specular pig (fontes à facettes) containing from three to six per cent. of manganese. In 1864 the regular production of spiegeleisen (fontes miroitantes), containing seven to ten per cent, of manganese, was inaugurated. At that time the Rhine was the only locality of this manufacture, and the Bessemer works of England and France obtained from Germany all their spiegel. From 1864 to the present time, the St. Louis furnaces have been advancing steadily the percentage of manganese in their product. From ferromanganese of thirty per cent. they had arrived, about two years ago, at a product containing seventy to seventy-five per cent., and for some time past they have been turning out what, as M. Jordan remarks, may fairly be termed fonte de manganese, or manganese pig, instead of iron, since the percentage of iron it contains is not more than 8.5, while the percentage of manganese is 85, or ten times as great. This very high grade material has a peculiar appearance, entirely different from that of ordinary cast iron or spiegel. It is granular, and steely gray in color. The following analyses, communicated to the Société to des Ingenieurs Oivils, by M. Jordan, show the composition of various products of the St. Louis furnaces :

Jan 1, 1878

By J. C. Crampton

Gradual shifts in the center of ore production have dictated three moves for the Pend Oreille Mines & Metals Co. plant. Capacity has grown from 300 tpd to the present 2400 tpd, and the gravity process used at the original Josephine mill has long since given way to improved flotation practice. The Josephine mill, operated in World War I and converted to flotation in 1927, treated 200,000 tons of ore rating as high as 16 pct Zn. By 1935 extra ore handling warranted construction of a new mill on a lower level, and capacity was raised from 300 to 800 tpd.

Sep 1, 1955

By G. B. Pryde, R. M. Magraw

In laying out a new mine, provision should be made for the ultimate recovery of as much coal in any given bed as is consistent with safety and economic mining. Though each mining district, if not each individual mine, has problems that make the adoption of any hard and fast rule impossible, certain basic principles are adapted to practically all conditions. One of the most vital is the provision for barrier pillars of ample dimensions to protect all haulage and permanent airways during the life of the property. Where conditions permit, room or butt entries should be driven on the strike or slightly to the rise, and rooms turned at right angles to these entries. The width of rooms and room pillars is governed by conditions prevailing in the mines under consideration. A safe rule is: In advancing, extract not more than 25 to 35 per cent. of the entire seam; in exceptionally thick seams, considerably less than 25 per cent. should be taken. Rooms usually vary in length from 250 to 350 ft. (76 to 106 m.) with a barrier pillar of not less than 80 ft. between the last crosscut. in rooms and the back entry of the level above. All entries, rooms, and entry-and-room crosscuts should be driven .on sights and room crosscuts should be driven at, right angles to the direction of the rooms. In mines under excessively heavy cover or where roof conditions are bad, rooms should be driven narrow and a barrier pillar left at every fifth to tenth room. This barrier should be of such dimensions that one or more rooms, with pillars of usual dimensions, may be turned through it when the barrier is no longer required. Two of the advantages of such a barrier are the protection of the panel against peaking of roof load during pillar extraction and the easy closing of the entry in case of fire. Where economic conditions permit, it is preferable to follow the retreating panel system of mining. In the case of coal that outcrops, and even in cases where no outcrop is exposed, it is preferable to commence pillar extracting on the high side of the mine. Where the retreating

Jan 1, 1922

Your esteemed favors transmitting my discharge as your representative on the War Minerals Committee have come duly to hand and the kind words of commendation contained are greatly appreciated. Like other war committees, The War Minerals Committee's business in Washington was to meet an emergency as best it could, and as soon as the emergency had passed pressure of personal responsibilities immediately scattered the individual members. A detailed report of the Committee's work is therefore impossible. But before the matter is closed I feel it incumbent on me to ask you to report to the Directors and the Council, and through them to the members of the Institute and of the Society, the inestimable value to our Committee of the unstinted support given by both your officers and members. The instant response to all requests for funds was of the greatest assistance in getting started with office force, stationery, etc., and led later to a regular organization in the Bureau of Mines, working under a special appropriation, which is still doing good work as the War Minerals Investigation under Dr. Spurr. The voluntary work of the special sulphur and manganese committees formed by the War Minerals Committee was of great value to the Government. Copies of private reports supplied were of much assistance. But the great service of engineers and geologists as a whole was rendered in connection with the passage of the War Minerals Bill by Congress. Though every assistance possible was rendered by the Bureau of Mines and the Geological Survey, by the close of 1917 our Committee had about reached the limit of its usefulness in the way of stimulating the various Government executive committees, bureaus and departments to a realization of the country's need of preparation for domestic production of "war minerals" and had found that special Congressional action was imperative if the war was to continue for anything like the time then generally feared. This was necessary not only 'to insure a. supply of war minerals but to make possible the appointment of some able mining administrator of large experience in the mineral industry who, with ample authority, could sit in the councils of the Government and see to it that the ever increasing autocratic powers the war was developing were used toward the mining industry so as to foster rather than crush the latter in its effort to produce sufficient raw material for war and essential civil requirements.

Jan 7, 1919

By AIME AIME

Air transport supplants the old methods. The 3-piece canoe fits in the plane and likewise makes possible not a bad division of labor over a 5-mile portage

Jan 1, 1933

By S. A. Ford

I would like to call the attention of our Bessemer steel manufacturers to a few facts in regard to the action of the manganese in the spiegel with the oxide of iron in the blown iron. The oxygen is united with the iron as a magnetic oxide, as Gautier asserts, and this oxide is reduced to a protoxide by one atom of the manganese uniting with one atom of the oxygen of the magnetic oxide of iron. This oxide of manganese and the protoxide of iron thus formed unite with the silica which has been formed by the oxidation of the silicon in the pig iron. Mr. Snelus and others

Jan 1, 1881

By W. E. STOKES

COMPANIES operating airplanes have had a relatively prosperous year, permitting them gradually to re- place old types of equipment. The pre-eminence of American-made planes, engines, and accessories has been challenged, either by foreign designs or by domestic patterns that have, for one reason or another. been licensed for manufacture abroad.

Jan 1, 1938

J. J. CARRIGAN, Butte, Mont. (written discussion*).-I think all who have had experience in the operation of metal mines will agree with Dr. Lanza that many improvements can be made in the underground workings to improve health conditions. Physical examination would no doubt be a good thing and would do a great deal in abating the diseases now so common among metal miners, but I cannot see how it would be possible to put this examination into practical working order. Dr. Lanza says, "For the sake of argument, this physical examination should be under state supervision." I think if, this were attempted it would result in nothing but argument. While such a law possibly could he passed in a few states, I feel certain that in the greater number the miners would fight such legislation with the same determination that they would

Jan 4, 1919

By Tayler H. Bingham

Personal consumption expenditures represent roughly two-thirds of total of GNP. While these expenditures directly account for only a small portion of total natural resource consumption, they account for a significant proportion indirectly. The reason is that all economic activity can be shown to be interrelated and that the intermediate production sectors, which are the primary users of natural resources, represent the interindustry transactions necessary to produce all final goods, including consumer goods. This paper provides a discussion of the methodology and quantitative estimates in physical units of the interrelationships between 15 major nonenergy resources and 6 energy resources and 477 personal consumption expenditure items.

Jan 1, 1977

Fifty to 75 million years ago, hydrocarbon-bearing rocks were formed in the Green River formation of Colorado, Wyoming and Utah. The hydro- carbons can be extracted from these rocks, marl- stone but misnamed oil shale, after crushing and intense heating. At about 900°F the marlstone decomposes to produce liquid shale oil. A press release from the Colony Development Co. describes a process which may permit, for the first time, economically feasible access to shale oil. Shale oil has resisted economic extraction for almost three centuries. According to the USBM, a patent was issued as early as 1684 in England to produce "oyle from a kind of stone". France produced oil from marlstone in 1838 and a dozen years later, Scotland started an oil shale industry, producing kerosine, that lasted nearly 100 years. In both countries, the process involved crushing the stone and retorting it to decompose the kerogen-a long and costly process at that time. In 1859, Edwin L. Drake brought in the first oil well in Titusville, Pa., and shale oil faded into oblivion.

Jan 8, 1965

1. Any society of undergraduates at a technical school, comprising students in any branch of engineering, metallurgy, chemistry, geology, etc., may be recognized by the Board of Directors in its discretion as an Affiliated Student Society, and its name, together with the names of its President and its Secretary, may be published in the Bulletin or the Year Book of the Institute. The individual members of such a society will not be catalogued as individual members or associates of the Institute, but may at any time be proposed for election as members or associates of the Institute, in the usual way. 2. Membership in an Affiliated Student Society, certified by the official representative thereof, and accompanied with suitable testimony as to character and qualifications, will have special ,weight with the Membership Committee of the Institute, in its consideration of the proposal of a candidate for membership or for Junior membership.

Jan 1, 1923

By J. M. Mutmansky, T. K. Greer

This paper takes a look at the optimal velocity to be used in coal mine entries and determines a statistical relationship for optimal velocity that can be applied under current mining conditions. This relationship provides the optimal velocity for coal mine airways under variations in power cost, mining cost differential, airway friction factor, time value of money, airway lifespan, and quantity of air carried. This enables the ventilation engineer to make an easy, rapid determination of the optimal velocity for planning purposes.

Jan 1, 1985

By Robert L. Grayson, Y. J. Wang, R. Mike Mishra

Prediction of ventilation needs in long range mining projections requires serious consideration when formulating those projections. Predicting the behavior of the ventilation system of an old, complex mine poses an especially provocative problem. Air-flow around and through mined-out areas via bleeder systems, leakage flows through stoppings or other air control devices, and the use of multiple fans all add to the basic complexity of a ventilation system and make predictions of ventilation changes very difficult. Fortunately, the task of making ventilation decisions can be greatly assisted by ventilation surveying and computer simulation. The Nemacolin Mine of Jones and Laughlin Steel Corporation, located in Southwestern Pennsylvania, is one such old mine which used the computerized approach successfully. A mine-wide pressure-quantity survey was used to obtain realistic values for airway resistance factors. These values, together with network topology, formed the basic input for computer simulation. Results from this simulation indicated that air quantities generated at critical airways by the model were generally within a couple of percent of those measured in the actual survey. It was then concluded that the model was acceptable for practical application, and it was used immediately for studying the effects on the ventilation system of changing the blade settings of fans. Additionally, the model was modified to incorporate projected mine development and used to predict future ventilation.

Jan 1, 1982

By T. M. Allen, W. H. White

THE Greenwood-Grand Forks area of southern central British Columbia, known as the Boundary District, has a long history of mining exploration and production. At the turn of the century this was the premier copper mining camp in the British Empire, its total production amounting to some 20 mil- lion tons. Most of this ore came from the great Granby mines at Phoenix, but the Motherlode mine at Deadwood camp, 6 miles to the west, and several mines in Summit camp, 5 miles north of Phoenix, made important contributions. The large deposits were exhausted in 1918 and the district since has seen only desultory exploration and salvage operations. The orebodies are mineralized skarn zones in limestone members of a thick series of Upper Paleozoic sedimentary and volcanic strata. Chalcopyrite is the primary ore-mineral. Copper carbonates and silicates occur sparingly in outcrops, but the oxidized zone generally is very shallow. Much of the surface is mantled by glacial drift which in most places ranges in thickness from 2 to 15 ft. In some of the hanging valleys, however, the glacial drift may be as much as 100 ft thick and may assume drumlin-like forms.

Jan 1, 1954

0PINION was general that this year's meeting of the Institute of Metals Division was one of the best in its history. In addition to its full and exceptionally fine program of professional papers, there were several other features of general interest-an in-spiring annual lecture by Dr. Cecil H. Desch which appears in abstract elsewhere in this issue, Mr. Sing-master's talk on the zinc industry at the annual dinner, and the presentation of the James Douglas Medal to one of the members of the Division, Dr. Zay Jeffries. Four technical sessions of the Division were held, dealing respectively with zinc, copper, aluminum, and general metallography, and in addition there was a joint session with the Non-ferrous Metallurgical Committee of the Institute. All of the papers presented were at-tended with much interest and followed by considerable discussion. The papers on plastic deformation of zinc by Messrs. Mathewson and Phillips, Romig, and Hoyt were of particular interest and awakened an extended discus-sion. They well illustrated the progress which is being -made today in the understanding of the mechanism of flow of metals, and the ingenuity of the authors in their crystallographic method of attack of this difficult problem was quite generally admired. A very old subject was treated in a modern way by Messrs. Corson and Bain in two papers on the harden-ing of copper and copper alloys. There has always existed a myth that the ancient Egyptians were masters of an art not possessed by ourselves; viz., that of hard-ening copper. This myth must have been quite defi-nitely dispelled in the minds of all those who listened to this admirable paper. Mr. Corson has applied the modern art of precipitation hardening to this old prob-lem with substantial success, employing small amounts of chromium, nickel, silicon, and cobalt for this purpose. The commercial application of these very important .developments of Mr. Corson is being actively investi-gated at the present time.

Jan 3, 1927

By S. A. Ford

A SHORT and accurate method for the estimation of manganese in iron and steel is of great advantage to Bessemer works, and I think it may be of interest to some of the members of the Institute to give in detail the process in use in the laboratory of the Edgar Thomson steel works. The process is based on the reaction first described by Beilstein and Jawein.* The steel, spiegel, or iron is dissolved in strong nitric acid, sp. gr. 1.½. Evaporation to dryness is not necessary, unless the amount of silicon is large, as in the case of certain pig irons. Then, as a clogging of the filter in the subsequent filtration is apt to follow, dissolve first in a dish in hydochloric acid, quickly evaporate to dryness, redissolve in the strong nitric acid, boil, and while boiling throw in crystals of chlorate of potash from time to time. Violent action ensues, yellow fumes are given off, and binoxide of manganese is precipitated, since it is insoluble in strong

Jan 1, 1881

THE relation of labor to the accident rate in mines is admirably epitomized by Thomas T. Read in his paper presented at the St. Louis meeting, in the sentence "Reliance for accident prevention must be upon the individual worker himself." In connection with the inspection of mines for the fixing of merit premium rates for insurance under workmen's compensation, it has been the practice of The Associated Companies to allow 60 per cent.of the credits for safeguarding of the physical hazards of the mine and 40 per cent. for the human element. By "human element" is meant. that inherent tendency of the industrial worker to be careless, negligent or disobedient, in respect to his own safety, and after that also f his fellow workman. This is a tendency not only of the laborer or of the skilled miner, but of all human beings, working or traveling, anywhere. This element of mine safety, sometimes called the moral hazard, has been admirably shown by statistics compiled from the records of the Department of Mines of the Union of South Africa to be clue in about equal measure to the carelessness of the miner and to that of the operator. These statistics show that about one-half the fatalities in mines are clue to the so-called hazard of the industry, or what is sometimes called the dangers inherent to work or misadventure. Of 2497 fatalities investigated, including over 200,000 employees, for a period of over 2 ½ years, it was found that 17.5 per cent. were due to faulty plant or material, fault of the foreman, or of the management-in short were-clue to the operator; 17.1 per cent. to disobedience of orders, carelessness or ignorance of injured persons; and 5.9 per cent. through fault of others, including fellow workmen. The fault of the operator is evidenced by failure to give proper warning, failure to inspect, failure to furnish proper equipment, and neglecting to comply with the recommendations of the inspector. That education and training of the mine operator as well as of the mine worker

Jan 2, 1918

By J. H. Hamilton, J. R. Lewis, J. H. Dismant, W. M. Fassell

RECENTLY this laboratory undertook the task of preparing some low carbon metallic cobalt by the carbon reduction of precipitated cobalt oxides. The oxides came in two lots and had the compositions given in Table I. Industrially, cobalt rondels' are made by the carbon reduction of cobalt oxide in small reverberatory furnaces at temperatures near but not above 1050 °C. This is a slow and tedious small batch process but does give cobalt metal which is low in carbon (1 pct C). Inasmuch as these cobalt oxides were relatively low in copper and iron it was decided to reduce them with petroleum carbon in a small three-phase electric arc furnace of about 3 to 5 Ib of metal capacity. It was hoped such a procedure would save considerable time and perhaps also indicate an improved commercially feasible process. The furnace was preheated by using small pieces of carbon electrodes to maintain the arc until a temperature of 1500°C was reached. The broken pieces of electrodes were then removed and 500 g of the cobalt oxides and 60 to 100 g of petroleum coke added. At the end of the reduction reaction, a high lime flux was added to the furnace to facilitate the removal of sulphur. Due to the fineness of the cobalt oxide powder used and also to the presence of chlorides there was considerable dust lost in charging the furnace. This was overcome by preparing briquettes composed of the cobalt oxides, charcoal, and a little bentonite to serve as a binder. The results obtained are summarized in Table 11, which shows that the cobalt metal produced in the arc furnace was high in carbon varying from 2.5 to 3.5 pct. This, of course, is much too high. For certain uses, such as in the preparation of permanent magnets, the carbon content of cobalt must be low. It was necessary therefore to find an effective method of reducing the carbon content of the cobalt that had been prepared in the arc furnace. Van Arkel3 recommends the use of Co2O3 as a means of removing carbon from cobalt. Experiments by the authors indicate that carbon is removed with difficulty by this method. Other methods used, including lancing of the molten high carbon cobalt with a jet of oxygen, proved to be ineffective. The method finally used makes use of the fact that cobalt metal is decarburized by carbon dioxide at the temperature of the molten metal. Two methods were used: 1—carbon dioxide was bubbled up through the molten cobalt, and 2— molten cobalt was maintained in a carbon dioxide atmosphere. In the first method the gas was introduced below the surface of the molten metal by means of a quartz tube. A high frequency induction furnace was used to keep the cobalt molten in both of these experiments. This kept the metal somewhat agitated and no doubt was an important factor in hastening the decarburization 'process by the second method. Both methods gave satisfactory results as shown in Table 111. An interesting observation in connection with this 'work was that a small sample of carburized cobalt metal could be decarburized by heating it with an acetylene torch adjusted to give an oxidizing flame. This may have been due to the presence of carbon dioxide in the products of combustion. Samples of molten high carbon steel were decarburized by the same method and it is suggested that nickel and perhaps manganese can be decarburized in a similar manner. Additional work, including rate studies and other theoretical aspects of this problem, is in progress in this laboratory.

Jan 1, 1953

Jan 1, 1952